650B2 valve clearances

When people talk about shim wear, they must be talking about the shims that fit on the top of the bucket, like the KZ1000 and 750 twins. I don't see any way that a shim that fits under the bucket (650 and 750 fours) can wear.

I think the only reason you would need a micrometer is to measure ones that the marking is not readable.

One more thing you probably already know but I'll reinterate. When you do valve shims only do one cam at a time, remove all the cam caps, pull the cam up while keeping the chain tight on the chain going down into the engine, let all slack stay between the cams, then simply lay that cam in the center of the engine with the chain still on its sprocket. Do your shim swap, then carefully move the cam back into position keeping the chain tight going down into the engine. Tighten that cam up, then do the same with the other cam. The timing will never need to be reset doing it this way. Makes it a lot nicer, faster and safer all the way around.

Thanks Ron, a lesson learned the hard way last night. Off to the garage I go!

Well I took out the cam and shims, and guess what? The marked 2.35 shim measured as a 2.50!! :huh: I checked all the others to be sure, they measured as marked.

No wonder why that valve was tight, it had a shim that was 2 sizes too big.

I'm taking Ron and Chet's advice and never trusting a marked shim again.

I'm getting antsy to get back on the road because we are experiencing a warm week of high 60 degree weather.
Weeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee

Post edited by: OKC_Kent, at: 2006/02/02 21:33

Shim over bucket type shims don't wear out or show much wear when measured. The main reason to measure them is that the numbers tend to fade and become indistinct. When this happens, it is sometimes possible to mistake one number for another and sometimes they have no numbers at all from being installed with numbers facing the cam shafts. I use a caliper and measure mine and mark their values with an ink pen so they are just easier to read when go through a pile looking for a shim. The ink pen numbers are far easier to read than the original.

This was a shim that was new in the bag, marked from Kawasaki.

Good advice on the cams, Ron. For those of us with "automatic" cam chain tensioners, it would be a good idea to lock it before loosening the cams.

A another tip came from my drag racer neighbor last night. He said that a good way to keep the timing is to run a zip tie trough the hole in the cam sprocket to keep the chain on it.

Doing these things ought to make swapping shims fairly painless.

- Nate >>